Wine Filtration-Do it yourself filter system and why to use it

By Don Schiller

Whether to filter or not has been debated by winemakers as long as
there have been filters. Some winemakers feel the only way to make
wine is the 'natural way', letting the wine clear on its own, even if
it does take a year or so. Other winemaker filter their wine to clear
it so they can bottle much quicker reducing chance of problems.

Why filter wine if it will clear on its own? A clear wine is more
appealing, the color is brighter. Filtering may make a wine drinkable
sooner. A sterile or fine wine filter will remove most yeasts that
may cause sediment and possibly refermentation. The disadvantage of
filtering is the possible reduction of color and tannins. These are
reasons why I don't filter red grape wines, but quickly filter fruit
or country wine and white grape wines.

There are several types of filters available, ranging from an
inexpensive gravity feed to fully closed pressurized multiple plate
filter system. This system is used by high volume wineries. A big
disadvantage of gravity feed is the introduction of oxygen and
bacteria. The closed pressure system eliminates the oxygen contact,
but it is far too costly for most home winemakers. The home winemaker
needs something between the two filters. I have designed a filter
system that is motor driven, low priced, and is easy for the handyman
to build in a couple hours.

If you build this wine filter, read and understand all instructions
before going to the store to buy parts. First thing needed is a self
priming pump. Self priming does two things, it will draw the wine
into the pump without needing to manually siphon it, and will create a
better pump output pressure. A small motorized pump is available from
many fleet stores, or better hardware stores. I used a SIMER #M40
that will pump about 360 gallons per hour, on sale for about $60.00.
The bad part of this pump is that the pump instructions tells you to
oil the pump before using. DO NOT oil this pump. While running
liquid through this pump, lubrication is not a problem. If you do
need to lubricate the pump, you may consider opening the pump and
using some glycerin or a small amount of vegetable oil to lubricate.
If you can find a pump system that is rated food grade and can deliver
about 25-40 psi, that would be better.

For the filter housing I used a house in line water filter. I picked
an inexpensive filter unit for about $10.00 plus the wrench for a few
dollars more. Some housings are clear, some not, it should not make a
difference which you use. Be sure to get one with 3/4" pipe
connections that will take the standard 10" filter cartridge.

To connect the system up, you will need tubing and connectors. The
connectors must mate with the connectors on the pump and filter
housing. If you use any other parts or equipment, make sure all
connectors match. The pump I picked needs two plastic garden hose
connectors for the pump inlet and outlet. For the filter housing I
found two plastic connectors with a 3/4" male thread on one end, the
other end has a barbed push on end. The barbed end holds the plastic
tubing. The tubing I used is food grade vinyl tubing, 5/8" inch
diameter. You may need 10-15 feet depending on your setup.

A pressure gauge between the pump and the filter will help you
determine when the filter is plugging. The gauge is not a necessity,
but is nice. If you do decide to put one on your system, use one that
is rated for 60 psi or less. You will also need a "T" barbed push on
connector for a pressure gauge if you use the gauge. Match the "T"
ends to all other connections.

A filter system without a filter cartridge is not much more then a
fast way to transfer wine. For filtering, you need a 1 micron or
finer cartridge. I have in my wine cellar a set of 10" cartridges
include 1.0, 0.45, and 0.2 nominal micron sizes. I use the 1 micron
size for preliminary filtering, but use the 0.45 or the 0.20 micron
for finer filtering. I ordered my cartridges from Presque Isle,
1-800-488-7492 but other suppliers may also carry the filter
cartridge. The filter cartridges can filter 50-600 gallons of wine
depending on the cartridge and the wine being filtered. See
information at the end of the article about a cartridge storage
container.

Miscellaneous Parts. You will need 5 hose clamps that will fit over
the tubing when installed over the barbed connectors and a little
Teflon tape to install the filter connectors.

Hooking it all together. I first started by making a frame on which I
could mount the filter and pump. I used a piece of plywood 1' X 2' X
1/2" and built supports to make a stand. I used a couple hooks and
straps to hold the filter onto the plywood. I secured the motor/pump
to the plywood on the opposite side of the filter. Next, using Teflon
tape, install the 3/4" barbed filter connectors into the filter input
and output openings.

Measure the distance between the pump output and the filter input.
This will be about 1-2 feet long allowing for a bend radius. Cut a
piece of the tubing to length, and two more pieces about 2" long.
Heat the two short pieces and one end of the 2 foot tubing in boiling
water for a few minutes. CAUTION, THIS TUBING IS HOT AND CAN BURN IF
HANDLED IMPROPERLY. This will soften the tubing enough to allow you
to push it over the barbed ends of the "T" connector for the gauge.
Connect the tubing from the "T" to the filter input connector you have
already installed. The gauge is connected onto the tubing on the tee
end. Install a garden hose clamp to the other end of the long tubing.
(SEE DRAWING FOR TUBING CONNECTIONS)

There are two other pieces of tubing needed, the supply tube and the
output tubing. Determine the length of tubing needed from your supply
carboy into the pump. Cut the tubing to length (or cut the remaining
tubing in half), and install a garden hose clamp on one end. Screw
that end onto the pump input side. This is your input or supply hose.
Take the other tubing and heat one end in boiling water, again being
careful of the temperature. Push the tubing onto the barbed end of
the filter output connector. This is your output hose and will output
filtered wine into a clean carboy.

Secure all connections to the pump, filter housing and gauge using
hose clamps where needed. Fill a bucket with 5 gallons water. Add a
1 teaspoon metabisulfite to the water. Put both the input and output
hoses into the water. With no filter cartridge installed in the
housing, plug in the pump motor power cord. The water will be pumped
throughout the system cleaning and sterilizing it. Run this 5-10
minutes, flushing out the system and checking for leaks. Remove power
and seal any leaks that you find. Dump the water, and refill with
clean water. Run pump again for a few minutes to flush system.
Remove power and drain water from tubing and filter housing.
(Optional-rather then plugging and unplugging the motor power cord,
you could add a switched outlet to the wooden frame. Use the outlet
and switch to turn the motor on and off.)

To filter wine, install a cartridge into the filter housing. Put a
gallon of water and 1/4 tsp. metabisulfite into the supply carboy.
Put the input tubing into the supply carboy and the output tubing into
an empty output carboy. Run pump until supply carboy is empty. Rinse
the sulfite water in the output carboy. Do this each time BEFORE and
AFTER filtering wine-it cleans and sterilizes the system.

Rack the wine to be filtered into your supply carboy, make sure the
wine is balanced. Add a double strength metabisulfite to help reduce
oxidation, the filtering does have a tendency to bubble at the
beginning and end of the carboy. Plug in the cord for the pump motor.
The wine will be filtered and pumped into the output carboy. Remove
power when the supply carboy is emptied. Bottle your filtered wine.

Since you may not be ready to filter as much wine as the cartridges
can filter, you might want to make a container to store the
cartridges. Using 3 inch PVC pipe, cut to about 12 inches for each
cartridge you want to store. Cement a cap on one end, and make a
removable coupling on the other end. The cartridge can be stored in
the pipe in a solution of 1200ppm metabisulfite in water.
Don Schiller